Q. How do I make a resonant oculus, and what can I use it for?
A. The ritual for making a resonant oculus can be found as you exit the Mechanica Lab, in Lab Hall Southwest:

> take sheet
(the discarded sheet)
Somebody has dropped yet another alchemical recipe. Oh, this is useful - you've used an oculus
before, but never learned to create one.

"TO CREATE A RESONANT OCULUS (an exceptional tool for observing unseen influences):
Prepare an environment with lunar influences. This will require a bound with a gestalt shelf;
place any lunar symbol on the shelf, but take care to exclude contaminating aromas. Then place
a glass loop within the bound and begin with a simple sealing. Vocalize a resonant tone to tune
the loop in the Celtic mode, followed by a syllable of counterbalance to fixate it."

You're not sure what tone and syllable the recipe is referring to. But the mention of the "gestalt
shelf" jogs loose a memory of another lecture.

> recall facts
> recall lecture on gestalt shelves
Aromas are one way to set the environmental influences for a ritual. For more precise control,
you can use a gestalt shelf - if the ritual bound has one. (Not all do.) By placing specific items
on the shelf before the ritual begins, you can apply precise symbolic markers to the
environment.

OK, so we need to find a glass loop, but also importantly, the resonant tone and syllable of
counterbalance formulas. The glass loop is in the Mechanica Lab, and you will find both formulas in the
Library:

> take neat sheet
The paper explains how to sing a resonant tone, which resonates with the structure of matter.

> take untidy sheet
It's another alchemical recipe. "A POTION to RESIST ALL INJURY BY HEAT OR FIRE: This
compound protects the drinker by balancing heat against cool - these symbolized by opposing
aromas. Place a measure of saline into a bound. Employ the simple sealing with no aroma
present. Release a fiery aroma; invoke counterbalance; change the atmosphere to chill; invoke
an elementary word of binding."

You recall, from an unusually digressive lecture, that one never uses the chymic retort for
potions intended to be drunk.

You memorize the instructions, including the syllable of counterbalance. You also add the sheet
to your bundle of paper.

Next, we need to find a bound with a gestalt shelf. There is one in the Pyrics Store, but be
careful! It is made of bricks, which will provide an 'earthy' influence. Remember that the recipe for the
oculus cautioned against this: "...but take care to exclude contaminating aromas". So the bound you
want to use for this ritual is located in the Optics Annex. But first there is one more thing we need,
something with "lunar influences":

> find silver coin
> x it
It's a worn silver coin. One side is stamped with a crude grinning moon-face. The other seems to
be a fish.

Well, turns out you get more bang for the buck from this simple
object than from almost anything else in the game:

> x coin through oculus
When viewed through the oculus, the silver coin displays a lunar nature.

Odd. You notice a spark in the oculus, as if it were reflecting some light not present.

What the oculus does is reveal the alchemical nature of simple objects. We already guessed that the
silver coin had a lunar nature due to the image of the moon cast on one face of it. But the oculus
confirms this. This is a dead handy capability to have, because as we progress through the game you will need
to find objects with lots of different influences to place on gestalt shelves, and the oculus is the most
reliable way to determine the nature of an object. But there is another thing the oculus can reveal which
is alluded to above: "Odd. You notice a spark in the oculus, as if it were reflecting some light not
present." So every time you walk into a room for the first time (whether or not you are prompted by a
reference to a spark!), you should remember to do the following:

> look through oculus
You peer through the oculus. Everything acquires a colorful, hazy fringe.

Wait. There's something else.

It wasn't visible to the naked eye, but the oculus reveals a cyan spark floating in the air.

> x spark
You focus on the cyan spark through the oculus. It's just a point of light, but...

A memory obtrudes. It's an alchemical lesson, but not one you ever attended; perhaps not in any
classroom or laboratory you've ever seen. The details are unclear - and yet the lesson is vivid in
your mind. The text being read describes an alchemical tool. "TO CREATE LAVELLE'S
LODESTONE (to locate elementally pure substances): Prepare a lunar environment, but with a
contaminating aroma. (This may require additional lunar symbology to outweigh the
contamination.) Place a silver thread within the bound, and apply a simple sealing. Speak a
word of essential nature; remove the aroma from the atmosphere; invoke a Minor Animus.
When held and swung, this invaluable lodestone will direct itself towards a nearby source of
pure elemental substance."

You consider these memories, including the Minor Animus.

Not every room has a hidden spark like that which triggers a memory, but a lot of them do, and
you won't be able to complete the game unless you find every spark that triggers a memory of a ritual and/or
formulas. In fact, every time you reset, you'll find that the first thing you should do after that is:

> create oculus

And there's a final thing of note concerning the resonant oculus. Once you have it, then:

> recall rooms

will tell you all the rooms you have visited that you have not yet checked for sparks :-)